HAO Colloquium - Odele Coddington, CU LASP

The NOAA Solar Irradiance Climate Data Record: From modeling solar irradiance based on SORCE observations to extending our understanding of solar irradiance variability with future TSIS-1 observations

A new version (version 2) of the Naval Research Laboratory’s (NRL) models of solar spectral irradiance (SSI) and total solar irradiance (TSI) were released to the public in 2015. These models, respectively called NRLSSI2 and NRLTSI2, form the Solar Irradiance Climate Data Record of NOAA’s National Centers for Environmental Information (NCEI) Climate Data Record (CDR) Program. The models are formulated using a multiple linear regression approach using nearly a decade’s worth of TSI and SSI observations from NASA’s SOlar Radiation and Climate Experiment (SORCE) mission and proxies of facular brightening and sunspot darkening. The model time period covers 1610 to present day. LASP operationally produces the Solar Irradiance CDR, delivering preliminary daily- and monthly-averaged TSI and SSI, and their associated time and wavelength dependent uncertainties, to NOAA NCEI on a quarterly basis and replacing the preliminary irradiances with final data on an annual basis. Yearly-averaged irradiances are delivered on an annual basis. 

In this talk, I will discuss the model formulation including uncertainty estimation and show comparisons of solar irradiances over different solar activity time scales with the original NRL model, solar irradiance observations, and with the Spectral and Total Irradiance Reconstructions (SATIRE) model.  I will then discuss the approach to incorporating new research advances, such as the revised sunspot number record, into a new revision of the Solar Irradiance CDR and the impacts of these advances on the long-term solar irradiance record.  Finally, I will discuss the future Total and Spectral Solar Irradiance Sensor (TSIS) instrument design changes and pre-launch calibration approach that will result in accuracy and precision improvements with respect to SORCE observations and the anticipated role of these TSIS observations for constraining the NRL solar variability models.

Date and time: 
Wednesday, March 1, 2017 - 1:30pm to 2:30pm